Stress-enhanced conductivity of polyethylene

The resistivity of polyethylene including voltage stabilizing additives is higher than that of the base material with no additives. In the experimental copolymer, however, the addition of a stabilizer decreases the resistivity. This phenomenon is being further investigated. All of the polyethylenes exhibit an increase in conductivity with increasing applied stress. This characteristic is beneficial in a d.c. cable, since the stréss thereby tends to equalize through the wall, or at least to show less variation than it does in the a.c. case with capacitive distribution. This enhancement of conductivity apparently does not exist for the experimental copolymer.